Transportation system for sheet delivery between sheet or sheet stack processing equipment

ABSTRACT

A sheet or sheet stack handling system for performing at least one operation on successive sheets or stacks of sheets, and interface for the same, wherein the document handling system includes at least two modules selected from a group consisting of an elevator transfer station, a modular transfer station, a storage station, a transportation cart, and a modular processing station. When more than one modular processing station are coupled to form the document handling system, the system may be utilized to perform a series of operations on successive sheets or stacks of sheets. Alternately, the individual processing stations or a group of the processing stations may be utilized to perform only certain functions on the sheets. The modules each contain a plurality of parallel, spaced, elongated support surfaces that form a sheet support surface. The parallel, spaced, elongated support surfaces of the two modules are sized and disposed that they may intermesh to allow a transfer of sheet stacks between the modules when one set of parallel support surfaces is moved upward or downward relative to the other.

FIELD OF THE INVENTION

The invention relates to a document processing system utilizing a transport system for passing sheet stacks between processing modules to provide optionally modular post-printer document processing.

BACKGROUND OF THE INVENTION

In the sheet finishing industry, sheet stacks are transferred between processing equipment as various steps are performed on the stacks of sheets. This transfer is typically classified as “in-line” or “off-line,” and sometimes “near-line.”

“In-line” refers to two pieces of processing equipment having their sheet paths joined together such that individual sheets are passed from one system to the other sequentially and processed as such. While there are many examples of such “in-line” processing, one such prominent example is designed following the Xerox DFA (Digital Finishing Architecture) Standard. The DFA protocol spells out mechanical and software specifications for attaching finishing machinery to DFA compatible Xerox sheet printers. Many vendors make secondary equipment to create systems using this standard, including Standard Finishing, C.P. Bourg, Duplo, and others.

“In-line” systems are advantageous in that they require minimal operator interaction, and therefore, have lower overhead and least opportunity for operator error. The entire system is locked in a one-to-one speed relationship, however, limiting the performance of the entire system to that of the slowest component. Accordingly, a major disadvantage of the “in-line” system is the lack of a buffer to allow for continued processing by some portions of the system if other portions of the system temporarily cease operations. Another disadvantage is reduced versatility from two types of processing modules that are complexly coupled, inhibiting their separate use for other functions.

“Off-line” refers to sheets being transferred in some non-automatic fashion, usually in stacks of sheets. Examples include simple carts to and from which sheet stacks are manually transferred by an operator. “Off-line” systems have the advantage of being able to match a slower module to a faster device, optimizing overall performance. It is commonly accepted that a ratio of 2:1 or greater may be matched with such in-line processing. Additionally, the components of such “off-line” processing are not tightly coupled, allowing for more versatile use of each module. “Off-line” processing, however, necessarily requires greater operator interaction than “in-line” processing, increasing labor costs as well as the opportunity for operator error in the form of both mechanical damaged sheet stacks or movement of the stacks out of sequence, when sequence is important.

“Near-line” refers to a special case of “off-line” processing where the carts are more elaborate and custommated to automatically receive and discharge sheet stacks. The stacks may be electronically tracked to ensure sequence of processing, as disclosed in U.S. Pat. No. 6,192,295 B1 to Gunther. One example of this type of “near-line” processing is marketed by GTI. In the GTI cart system, stacks are laid on a cart and the cart is manually rolled to a feeder. The GTI cart is designed to custom mate to the GTI stacker and GTI feeder. Although operator error is less than the opportunity with true “off-line” the chance is not eliminated. The GTI cart has a clamping system that secures the stacks from movement, however, the system requires considerable operator effort to operate.

OBJECTS AND BRIEF SUMMARY OF THE INVENTION

In accordance with the invention, there is provided a document handling system which utilizes one or more of an elevator transfer station, modular transfer station, transportation cart, storage station, and/or modular processing station to provide in-line document processing in a modular environment while allowing the use of one or more modular processing stations in an off-line manner without disconnection of the module from other modules that form part of the sheet handling system. Each of the transfer station, cart, and storage station includes a plurality of elongated support surfaces or fingers to create a sheet support surface, slotted platform or deck such that the alternating fingers and slots of the transfer station or cart storage station receive the alternating slots and fingers of the cart to transfer stacks of sheets supported on the upper surface to and from the cart and transfer station or storage station. Stacks of sheets may likewise be transported between adjacent processing modules by similarly intermeshed transfer stations or intermediate belts, rollers, or the like.

The transfer station includes a platform comprising a series of driven surfaces in the form of, for example, driven rollers or flat rotary belts, which are spaced to engage with a number of different structures. The transfer station may be a separate station or the transfer station components may be incorporated into a modular processing station. For ease of understanding, this application will refer to belts. It will be appreciated, however, that alternate designs, such as those utilizing a plurality of in-line driven rollers, are likewise form appropriate driven plurality of elongated support surfaces, and are to be considered to fall within the purview of the term “belt” as utilized herein. The spaced belts can intermesh with the slotted surface of a stacker, feeder, or other elevator mechanism such that the stack processing module can deposit or remove sheet stacks from the transfer station. Additionally, the spaced belts of the transfer station platform may intermesh with the slotted deck of the cart, such that the sheet stacks can be moved from one transfer station to another using the cart, without connecting the two transfer stations physically. Finally, the spaced flat belts of the transfer station platform can intermesh with the spaced flat belts of another transfer station or an intermediate station. Under these circumstances, the belts of the second transfer station are spaced at one-half pitch off that of its mate. In this way, transfer stations can be connected to form a conveyor between processing modules to transfer sheets or stacks of sheets, eliminating the need for manual intervention to move sheets or sheet stacks between processing modules during processing. The transfer station may be provided with an elevator mechanism that moves a stack of sheets supported thereon in a vertical elevation to provide the stack for further transfer or for further processing operation. It is further envisioned that preexisting processing stations may be retrofit with such transfer or elevator transfer stations to allow their integration into the document handling system.

The moveable cart would likewise have a slotted deck that could intermesh between the individual belts of the transfer station to form a joint sheet support surface. Preferably, the cart may be manually, electrically, hydraulically, or otherwise powered, and includes a mechanism whereby the cart deck can be raised or lowered by cam, lever, electrical power, hydraulics or other mechanism such that the cart may deposit a stack of sheets on the transfer station platform or raise a stack of sheets from the transfer station platform to remove the stack from the transfer station. Preferably, the cart includes a quick clamp release system to secure the sheet stack for transport. Additionally, the cart is preferably symmetrical such that a stack may be picked up or deposited from either side of the cart to readily provide phasing of the edges of the stack. The transfer station or elevator transfer station, as well as the processing modules themselves may provide for alternate movement of the support surfaces into or out of the sheet handling system to facilitate access by the cart. For example, the support surface or deck may move in a substantially perpendicular direction from the system to allow intermediate access to a stack of sheets. In this way, the cart may readily be utilized to access and remove a stack from the deck. The deck may then be retracted back into the system.

Finally, the storage station includes a slotted stationary platform where the slots are spaced to receive and intermesh with the slotted deck of the cart. In this way, the cart may be used to deposit the sheet stack on the storage station when the stack is not transferred directly to the elevator transfer station. The storage station may include upright stacking guides which may be adjustable or permanently spaced or installed. The stacking guide may also be removable for storage and to provide a tidy appearance. As with the elevator transfer station, the cart may be used to place a sheet stack on the storage station and the cart then lowered, leaving the stack on the storage station. Similarly, an empty cart may be intermeshed with the slotted platform of the storage station and the cart slotted deck raised to lift the sheet stack from the storage station for removal to an elevator transfer station.

While the cart has been described as including a movable deck, the storage station-and elevator transfer station may alternately include movable platforms for raising or lowering a sheet stack onto the cart having a stationary deck, or some combination of such arrangements.

The aforementioned document transport system facilitates an improved and novel document processing system. In particular, a modular transfer station mates with both processing module elevators and other transfer stations to allow a new version of “in-line” processing in which sheet stacks or individual sheets are passed automatically between processing modules with a relatively large buffer. The buffer allows large and numerous stacks to be placed between the modules allowing for considerable pauses in one module without a concurrent pause in the other modules in the inline process, and allows considerable mismatches in processing speeds between machines without forcing human intervention or modification of the modules to synchronize their processing speeds. Further, this movement between modules during in-line processing can take place without intervention by an operator and the incumbent risk of error.

Additionally, the cart that mates with the transfer station can be docked in one of two directions with the transfer station, allowing the operator to choose to reverse the processing orientation of the stack desired. The cart also includes a quick clamping system which allows the stack to be quickly secured without extended operator involvement.

Further, the same transfer station can be utilized for both a buffered version of in-line processing, and with the cart, off-line and near-line processing that requires little operator involvement.

In addition to the benefits provided by the document transport system in allowing the in-line processing system described herein, there are other salient features of the invention. For example, one or more modules that form the modular in-line processing system may be used in an off-line manner as well without disconnecting the relevant module(s) from the in-line system, or can be utilized as free standing, independent processing modules.

These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a plurality of elevator transfer stations incorporated into processing modules construed in accordance with teachings of the invention

FIG. 2 is a perspective view of a cart preparing to dock with an elevator transfer station constructed in accordance with teachings of the invention.

FIG. 2A is a schematic side view of the cart and elevator transfer station of FIG. 2 wherein the cart is docked with the elevator transfer station.

FIG. 2B is a front view of the cart and elevator transfer station of FIG. 2 a.

FIG. 3A is a schematic of cart docking arrangement in accordance with teachings of the invention.

FIG. 3B is an enlarged fragmentary view of the wheels and rollers of the cart of FIG. 3A engaging surfaces of the elevator transfer station of FIG. 3 a.

FIG. 3C is a schematic view of an alternate embodiment of a cart docking arrangement.

FIG. 3D is a schematic of a second alternate embodiment of a cart docking arrangement.

FIGS. 4A-F are bottom perspective or plan views of various wheel configurations for the movable cart.

FIG. 5A is a perspective view of a cart incorporating a cross bar operation mechanism.

FIG. 5B is an enlarged fragmentary front view of the handle and cross bar of FIG. 5A.

FIGS. 5C-I are fragmentary perspective views of various handle operation mechanisms, including buttons, levers, and cam locks.

FIGS. 6A-C are cross-sectional views of embodiments of locking arm uprights.

FIGS. 7A-D are fragmentary perspective views of various locking bar operation mechanisms, including buttons and levers.

FIG. 8A is a fragmentary perspective view of an alternate embodiment of a locking arm arrangement.

FIG. 8B is a cross-sectional view of the locking arm of FIG. 8A.

FIG. 9A is a fragmentary perspective view of a second alternate embodiment of a locking arm arrangement.

FIG. 9B is a cross-sectional view of the locking arm of FIG. 9A.

FIG. 10A is a fragmentary perspective view of a third alternate embodiment of a locking arm arrangement.

FIG. 10B is a cross-sectional view of the locking arm of FIG. 10A.

FIG. 11A is a fragmentary perspective view of a fourth alternate embodiment of a locking arm arrangement.

FIG. 11B is a cross-sectional view of the locking arm of FIG. 11A.

FIG. 12 is an enlarged perspective view of a storage station constructed in accordance with teachings of the invention.

FIG. 13 is a front elevational view of the storage station of FIG. 12.

FIG. 14 is a side elevational view of the storage station of FIGS. 12 and 13, and a cart prepared for docking.

FIGS. 15A-C are views of an alternate embodiment of a storage station.

FIGS. 16A-C are views of a second alternate embodiment of a storage station.

FIGS. 17A-C are views of a third alternate embodiment of a storage station.

FIGS. 18A-C are views of a fourth alternate embodiment of a storage station.

FIGS. 19A-C are views of a fifth alternate embodiment of a storage station.

FIGS. 20A-C are views of a sixth alternate embodiment of a storage station.

FIGS. 21A-D are views of a seventh alternate embodiment of a storage station.

FIGS. 22A-D are views of an eighth alternate embodiment of a storage station.

FIGS. 23A-D are views of a ninth alternate embodiment of a storage station.

FIG. 24 is a view of a tenth alternate embodiment of a storage station.

FIGS. 25A-B are views of an eleventh alternate embodiment of a storage station.

FIGS. 26A-B are view of an alternate embodiment of a platform and deck finger design.

FIGS. 27A-C are views of a second alternate embodiment of a platform and deck finger design.

FIGS. 28A-B are views of a third alternate embodiment of a platform and deck finger design.

FIG. 29 is a perspective view of an in-line document processing system constructed in accordance with teachings of the invention.

FIG. 30 is a schematic system diagram showing document transport and operations executed with the in-line document processing system according to an embodiment of the invention.

FIG. 31 is a flow chart detailing a process for managing document positioning in an embodiment of the invention.

FIG. 32 is an operational diagram of an exemplary user interface and related functions in an embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to the drawings, there are shown in FIG. 1 representative sheet or sheet stack processing module 30. The sheet or sheet stack processing module 30 shown is intended to be representative of any of the various types of modules, including finishing machines such as binders, inserters, envelope stuffers, sealers, punches, or any number of types of processing devices. Significantly, the sheet or sheet stack processing module 30 includes one or more transfer stations 32 for receiving either single sheets or stacks of sheets to be passed onto the processing module 30. The sheet or sheet stack processing module 30 may include a single transfer station 32 or a plurality of transfer stations 32 such as are illustrated in FIG. 1. The transfer station 32 includes a sheet support surface or platform 34 around which a belt 36 rotates to pass the sheets onto the sheet or sheet stack processing module 30. The platform 34 of the transfer station 32 may extend directly from the processing module 30 or the document processing system, as illustrated in FIG. 1, or the platform 34 may be moveable, by electronic, mechanical, or other mechanism, in an essentially horizontal manner from the processing module 30 for access to a stack of sheets disposed on the platform 34.

Turning to FIG. 2, in accordance with the invention, the platform 34 is slotted, having a plurality of alternating platform fingers 38 and platform slots 40, and the belt 36 includes a plurality of individual belts spaced to rotate longitudinally along the outer surface of the platform fingers 38. The platform fingers 38 are spaced such that they can intermesh with a slotted surface of sheet or sheet stack processing module 30 such as a stacker, feeder, elevator, or the like. In this way, the stack processing modules so equipped can deposit or renew the sheet stacks from the transfer station 32 for further processing. Additionally, the fingers 38 of the platform 34 are spaced such that they may intermesh with the platform fingers and slots 38, 40 of another transfer station 32. In this way, a plurality of transfer stations may be connected to form a conveyor between processing modules, eliminating the need for manual intervention to move sheet stacks.

In accordance with another feature of the invention, there is provided a moveable transportation cart 42 that includes a slotted deck 44. The cart 42 may operate electrically, hydraulically, manually, or by any other appropriate method. As with the transfer station platform 34, the slotted deck 44 of the cart 42 includes spaced deck fingers 46 having open deck slots 48 disposed therebetween. Significantly, the deck fingers 46 and slots 48 as well as the platform fingers 38 and slots 40 are spaced such that they may intermesh, as shown in FIGS. 2 through 2B, the deck fingers 46 being disposed in the platform slots 40 and the platform fingers 38 being disposed in the deck slots 48. Thus, sheet stacks disposed on the upper sheet support surface of the slotted deck 44 may be passed to the platform 34 of the transfer station 32, or the cart 42 may be utilized to sheet stacks disposed on the platform 34 of the transfer station 32. In this way, the cart 42 may be utilized to provide or retrieve stacks of sheets at one or the other end of a system of a plurality of coupled processing modules, or it may be utilized to remove stacks of sheets at intermittent positions from individual processing modules within the system.

In order to facilitate movement of the sheet stack between the slotted deck 44 of the moveable cart 42 and the platform 44 of the transfer station 32, at least one or the other of the slotted deck 44 or the platform 34 is vertically moveable relative to the other. In the currently preferred embodiment, the slotted deck 44 is vertically moveable relative to the platform 34. In this way, the deck and platform fingers 46, 38 may be intermeshed and the slotted deck 44 either advance upward relative to the platform 34 to remove the sheet stack from the platform 34 or downward relative to the platform 34 to place a sheet stack on the platform 34. It will be appreciated, that this same function could be performed by movement of the platform 34 itself up or down vertically relative to the slotted deck 44.

In the currently preferred embodiment, when the slotted deck 44 is moved upward or downward vertically relative to the platform 34 and the cart body 50 itself Alternatively, the entire cart body 50 and the slotted deck 44 may be moved vertically upward or downward relative to both the platform 34 and the ground. This vertical movement may be accomplished by way of a cam arrangement, a lever, a gearing arrangement, electrical power, hydraulics, or other method to deposit or remove a stack from the belt system by any appropriate mechanism.

A number of cart docking arrangements may be provided to facilitate movement of the cart into position and to facilitate the intermeshing of the deck fingers 46 and the platform fingers 38. A few such possibilities are illustrated in FIGS. 3A through 3D. It will be appreciated that these are only schematic renditions, and that the platform 34 of the transfer station 32 and the deck 44 of the moveable cart 42 will both include slotted surfaces designed to intermesh with one another.

In order to facilitate movement of the cart 42, the cart includes one or more wheels, rollers, casters, or the like 52 which extend from the cart 42 to contact the ground. As shown in FIGS. 3A and 3B, the cart 42 may include sets of wheels disposed at various distances from the ground. In this embodiment, the cart includes a large pair of wheels 52 on either side as well as two pairs of smaller casters 54. The transfer station 32 includes a pair of ramps 56 such that the wheels 52 are disposable on either side of the ramp 56. As the wheels 52 continue to roll along either side of the ramp 56, the casters 54 contact the ramp 56, and the cart 42 continues moving forward, lifting the wheels 52 off the ground. In order to further center the cart 42, the ramp 56 further includes a central raised guide 58 and the cart 42 includes rollers 60 which are mounted horizontally and disposed to contact either side of the central raised guide 58 as the cart 42 continues up the ramp 56.

Another cart docking arrangement is disclosed in FIG. 3C. In this embodiment, the cart 42 includes a pair of outwardly opening C-shaped channels 62 disposed along either side, and the transfer station 32 includes elongated rigid rectangular sections 64 along either side of the slotted platform 34. The rigid rectangular sections 64 preferably include a chamfered section disposed to the center and guide the cart 42 forward toward the platform 34. Additionally, the rectangular sections may include one or more rollers 68 disposed along one or more of the surfaces which engage the C-shaped channels 62 as the cart 42 is moved forward into the transfer station 32.

Yet another cart docking arrangement is illustrated in FIG. 3D. In this embodiment, the transfer station 32 includes a ramp arrangement 70 which includes a central channel 72 for receiving an alignment peg 74 extending downward from the moveable cart 42. The central channel 72 tapers from a relatively open section 76 distal the transfer station to a confined section 78 proximal the transfer station. In this way, as the cart 42 moves inward to the transfer station 32, the alignment peg 74 engages the open section 76 of the central channel 72 and is guided into the confined section 78.

In order to allow free movement of the cart 42 relative to the ramp arrangement 70, the ramp 70 includes a pair of rollers 77 disposed along either side of the central channel 72 as the ramp angles upward, and the upper surface of the ramp 70 includes a plurality of ball transfers 79 which allow the cart to move into axis relative to the transfer station 32.

Thus, it will be appreciated that the cart may have any number of potential configurations of wheels, rollers, casters, or the like. By way of example only, various potential wheel configurations are illustrated in FIGS. 4A through F. FIG. 4A is a configuration with a pair of large, straight wheels on either side of the platform and four casters disposed at four corners of the cart. FIG. 4B includes four casters disposed at the four corners of the cart with two inboard straight wheels and horizontal wheels disposed along one edge. FIG. 4C includes a pair of straight wheels disposed outboard the cart and a pair of casters disposed at the front and rear of the cart. FIG. 4D includes four casters disposed at the four corners of the cart. FIG. 4E includes a pair of straight wheels disposed outboard the cart along one edge and a pair of casters disposed at the opposite two corners of the cart. FIG. 4F shows a pair of straight wheels disposed outboard the cart along one edge with a single caster disposed along the opposite front edge. According to one aspect of the invention, the cart 42 is preferably symmetrical so that it may be docked at the transfer station 32 in either direction. It will be appreciated that the wheel and docking arrangements illustrated in FIGS. 3A-D and 4A-D are bi-directional in that the cart 42 could be docked with a transfer station 32 from either direction. Conversely, the wheel and caster arrangements shown in FIGS. 4E and 4F are mono-directional in that they would likely be docked only in one direction with the transfer station 32.

In order to facilitate easy movement of the cart 42 by an operator, cart 42 includes a handle 80 pivotably mounted to the cart body 50. The handle 80 is preferably of an inverted U-shape and may be locked in a vertical position or unlocked and swiveled to either side so that the cart 42 may be moved from either side. Unlocking of the handle would likewise release the brake on the wheels 52 to allow the cart to move forward or backward. The handle release mechanism may be in the form of cross bar 83 as shown in FIGS. 5A and B, buttons 84, 86 centered along the top or bottom of the handle 80 as shown in FIGS. 5C and D, or a button 88 disposed along the side of the handle as shown in FIG. 5E. Alternately, the handle release may be in the form of a lever 87, 89 centered or disposed along the side of the handle as shown in FIGS. 5F and G. or dual levers 91 as shown in FIG. 5H. Alternately, the handle release may be in the form of a swivel cam lock 93, as shown in FIG. 5I. It will be appreciated by those skilled in the art that these handle release arrangements are provided by way of an example only and are not meant to restrict the invention in any way.

The handle 80 may be formed by any appropriate means, and may include multiple components fabricated by different methods. For example, it may include extruded, cast, or molded portions and may be fabricated from plastic or metal, such as aluminum, for example, or any other appropriate material.

As may be seen in FIG. 2, the handle 80 is preferably pivotably coupled to the cart body 50 at a relatively low location. In this way, the application of a moving force by the operator creates a minimal moment, providing a stable arrangement with minimal opportunity for the cart 42 to be overturned.

In order to stabilize the sheet stacks on the upper slotted deck 44 of the movable cart 42, the cart 42 is provided with a locking arm arrangement 100. As shown in FIG. 2, the locking arm arrangement 100 can include a simple pair of uprights 102 disposed along either side of the deck 44 to which a selectively lockable sheet or sheet stack clamp or locking arm 104 is slidably mounted. In this way, once a sheet stack is placed on the slotted deck 44, the operator may unlock the locking arm 104 and slide it downward along the uprights 102 to contact the upper surface of the stack and to secure them into position on the cart 42 before movement. The uprights 102 have any appropriate structure, such as the simple bars illustrated in FIG. 2, or, for example, extruded hollow sections such as are shown in FIGS. 6A-6C. The embodiment illustrated in FIG. 6C further includes elongated channels 106 which may be utilized to store slidably enclosed guide rods 108. Guide rods allow stacking directly on a cart. The uprights 102, as well as the locking arm 104, may be fabricated of any appropriate material, such as plastic, steel, or aluminum.

As with the handle 80, the locking arm arrangement 100 may include any number of locking arrangements. In the currently preferred embodiment, the locking arm 104 includes a centrally elongated opening 110 which may be utilized as a handle for moving the locking arm 104 upward and downward along the uprights 102. The locking mechanism for the locking arm 104 may include arrangements such as a depressible button 112, 114 disposed along either the upper or lower surface of the handle portion 110 as illustrated in FIGS. 7A and 7B, or a depressible lever 116, 118 similarly disposed along either the upper or lower surface of the handle 110, as shown in FIGS. 7C and 7D. It will be appreciated, however, that alternate locking bar operation mechanisms may be provided.

The locking arm 104 may be constructed of any appropriate materials and by any appropriate method. For example, as shown in FIGS. 8A and 8B, the locking arm 104 may include a formed metal cross bar 120 with separate plastic or metal inserts 122 inserted through either side of the cross bar 120 in order to form the handle 110. For the sake of simplicity in this and the following illustrations of various embodiments of the locking arm 104, the sides are illustrated with a top and centered button 112 release of the lock to allow the locking arm 104 to slide up and downward on the uprights 102. The cross bar 120 may alternately be extruded from plastic, as shown in FIGS. 9A and 9B. As with the embodiment in FIGS. 8A and 8B, plastic or metal inserts 122 are received in openings through either side of the cross bar 120 to form the handle 110. Alternately, the cross bar 120 may be extruded with an ergonomic design which allows the user to grip the cross bar 120 for movement of the locking arm 104. Such a design is illustrated, for example, in FIGS. 10A and 10B. Further, the cross bar 120 may be formed in two or more parts which are then bolted or riveted together, as shown in FIGS. 11A and 11B. Such cross bar components may be either extruded or cast, for example. It will be appreciated, however, that alternate design arrangements of the cross bar fall within the spirit and scope of this application.

In accordance with another important aspect of the invention, there is provided a storage station 130, as is shown, for example, in FIG. 12. Storage station 130 includes legs 132, which in the preferred embodiment are of an L-shape, including a vertical portion 134 and a horizontal portion 136. Feet 138 are preferably provided below the horizontal portion 136 of the legs 132. Spine body 140 extends between the upper ends of the vertical portion 134 of the legs 132. In order to receive and intermesh with the slotted deck 44 of the movable cart 42, a slotted platform 142 extends from the spine body 140 of the storage station 130. Significantly, the fingers 144 and slots 146 of the slotted platform 142 are spaced such that the slots 146 receive the deck fingers 46 to dispose the platform fingers 38 adjacent the storage station fingers 144 in alternating positions. In this way, the operator can transfer sheet stacks between the deck fingers 46 and the storage station fingers 144.

As shown in FIG. 12, in order to maximize storage space, a second spine body 140 a and slotted platform 142 a may be positioned adjacent the storage station 130. In this way, the adjacent storage station 130 a utilizes one of the legs 132 of storage station 130 and an additional leg 132 a. It will thus be appreciated that a continuous line of storage stations may be disposed adjacent one another in order to maximize storage space.

In order to provide added support to a sheet stack supported on the slotted platform 142 of the storage station 130, a back stop stacking guide arrangement 148 may be provided such as is shown in FIGS. 12-13.

As with the transfer station 32 and movable cart 42, the storage station 130 and related components may be of any appropriate design and material, and constructed according to any appropriate method. For example, those storage stations designs are illustrated in FIGS. 15A-25B. Legs, for example, may be extruded as shown in FIGS. 15A-C, stamped and formed as shown in FIGS. 16A-C or FIGS. 17A-C, formed of bent tubing, as shown in FIGS. 18A-C, FIGS. 19A-C, and FIGS. 20A-C, and may include side panels as shown in FIGS. 21A-B. The stacking guide may be a relatively permanent structure as shown in FIGS. 16A-C, a flip-up surface as shown in FIGS. 21A and 21B, or removable structure as shown in FIGS. 22A-D, FIGS. 23A-D and FIGS. 15A-C. The stacking guide may include adjustable components such as are shown in FIGS. 23A-B, FIGS. 24A-B, FIGS. 15A-C and FIGS. 16A-C. The slotted platform 142 may include chamfered or non-chamfered guiding arms 152 along either side of the fingers 144 as shown in FIG. 12, FIGS. 15A-C, and FIGS. 23A-D, or the platform 142 may lack such guide arms altogether, as shown in FIGS. 22A-D. Moreover, the spine body 140 can include a hinged cover 154, such as is shown in FIGS. 22A and 22B. According to this embodiment, the stacking guides 148 can be stored beneath the cover 154. The cover 154 itself can be extruded, molded, or stamped and formed.

The platform fingers 144 may be of an appropriate design and formed by any appropriate method. For example, the platform fingers 144 may be stainless rods, as shown in FIG. 23A. Alternately, they may be cast as shown in FIGS. 16A-C, or extruded, as shown in FIGS. 15A-B or FIGS. 26A-B. The extrusion may be a simple rectangular design with optional end caps as shown in FIGS. 27A-C, or a vertically extruded design with an optional cap as shown in FIGS. 28A-B.

FIG. 29 shows a perspective top side view of an in-line document processing system 2901 according to an embodiment of the invention. The system 2901 comprises a plurality of processing modules, such as modules for binding, inserting, envelope stuffing, sealing, punching, or any number of types of processing as described above. The illustrated example includes a tab cutter 2903, punch 2905, binder 2907, cover closer 2909, and book/face stacker 2931. The system 2901 also includes an offset stacker 2935 and cover feeder(s) 2937 to facilitate the stacking of the materials for processing and to provide document covers where needed for processing. Consistent with the above description, the cart 2933 is shown interfacing with the system 2901 at the book/face stacker 2931. In order to facilitate processing modules having disparate processing speeds, a buffer/transport system 2939 is shown disposed between a printer 2941, or other document source, and the rest of the system 2901. While not otherwise illustrated, such one or more buffer transport systems 2939 may be provided at other positions in the system 2901, that is, between other processing modules, in order to provide or enhance similar buffering between processes. The operation of the in-line system 2901, including the buffer/transport system 2939 will be described hereinafter, with the understanding that the processing modules 2903-2931 shown are exemplary and may be wholly or partially supplemented or replaced by other types of processing modules within the scope of the invention.

Initially, a print job or other process at document source 2941 produces one or more documents for processing. A document will generally comprise a plurality of sheets, but may in unusual cases have only a single sheet. The document source 2901 may interface to a document supplementation device such as tab cutter 2903. In the illustrated example, the tab cutter 2901 provides and inserts index tabs or other dividers into documents produced by document source 2901, either during or after document production. A plurality of such documents is then flush or offset stacked to provide a single stack or succession of stacks, each including a plurality of documents. The sheet stacks formed by this process, preferably including tabs where appropriate, are conveyed to the first process module 2905, illustrated as a punch 2905, via the buffer transport segment 2939.

The buffer transport segment 2939 is usable either to convey documents to the first process module 2903 for processing, or to divert incoming documents to a temporary storage space, or buffer. The primary reason for sometimes buffering the document stream in this manner is to facilitate in-line processing between modules with different processing or production rates. For example, in the illustrated scenario, the printer 2941 may produce documents at a faster rate than the punch 2903 can process such documents. In this case, the buffer would absorb the difference in capacity. In this manner, for example, if the printer 2941 produced documents twice as fast as the punch 2905 could process them, the buffer would absorb approximately half the documents produced while documents continued to be produced.

After document production at the source 2941 ends, the buffer may be gradually emptied as the rest of the processing system 2901 continues to run. It will be understood that the maximum time during which such a mismatch can be alleviated by buffering is tied both to the degree of mismatch and the document capacity of the buffer system. It is also within the invention to provide a number of buffers, such as a primary buffer and one or more overflow buffers for excessive or unexpected mismatches or surges in document production. Note that the buffer between a slower supplying module and a faster consuming module will generally not be used, except to facilitate intervening offline processing. That is, the rate mismatch must be buffered only when the faster module precedes the slower. Although only a single buffer/transport unit 2939 is visible in the illustrated example, such a transport and buffer system will preferably be provided at the junction of any two processing modules, unless the modules incorporate a mechanism for transport to the next module, and, in the case of rate mismatch, for buffering excess incoming documents.

Once the document processing system 2901 has finished processing one or more documents, the documents are output to a user accessible location such as to a cart 2933 as described above or otherwise. In the illustrated example, the finished documents will have been punched, bound (with closed cover), and stacked.

Note that one or more modules in the document processing system 2901 are preferably usable in an offline manner without disconnection from the system 2901. Such off-line use could occur during in-line processing by buffering in-line documents during the offline processing. For example, in the illustrated example, the punch module 2905 may also be used in an off-line mode by a user, via an access on the side of the module 2905. Alternatively, an offline stack of documents may be fed to the input belt by a cart or other appropriate method. Thus, the user may initiate an offline use of the punch 2905 via a user interface thereon. In response to user initiation, the punch 2905 preferably completes work on the current document being processed and then begins to buffer all incoming documents for a brief period while the user completes an offline use, such as by inserting a document or documents to be punched and then retrieving the punched materials. When the user has completed the offline use, the punch 2905 preferably begins again to process documents in an inline fashion, either from a buffer or directly from the preceding module.

Conveniently, all or a lesser number of the processing modules may be utilized in an in-line processing job. In this regard, if a particular processing module is not to be utilized, the individual lifts, sets, or stacks may proceed through the module along the standard processing line with the relevant function (e.g. the punch) disengaged. Alternatively, a bypass path may be provided through the module.

FIG. 30 is an operational diagram showing the functional elements of an inline processing system, as described above architecturally, and the operational relationships between those functional elements. First note the operator control interface 3001. This interface is preferably in the form of a graphical user interface that presents the user with a mechanism for becoming apprised of available values, settings, parameters, etc., and for selecting or setting such constraints accordingly. For example, a user may be presented with an interface for selecting which parameter to modify, one of which is a sheet size. After selecting the option related to sheet size, the user may be presented with an array listing available sheet sizings, at which point the user will select a desired size and complete the process. Other preferably modifiable constraints include a preferred edge for binding, whether or not a cover will be provided, the type of binding, if any, desired, and so forth.

The common elements tying major processing functions together are one or more transfer stations 3003. Documents to be processed are supplied initially via a transfer station or otherwise, generally in a stacked form, from one or more stackers 3005, 3007 and associated interface(s) 3011 where necessary. At that point, the stacked documents are supplied, preferably via a conveyor input as described more extensively above, to a feeder to be provided to the subsequent processing modules. From the feeder, the documents enter a first processing module such as a punch module 3015 for punching a series of holes through an edge of each document to facilitate later binding. 100911 Note that the punch module 3015 is shown as receiving one or more die sets 3017, which are used to define the precise manner in which the holes are made in the edge of each document. Further note that the punch module 3015 may also receive cover material from a cover feeder 3019 when desired. These covers are preferably associated with each document prior to actual punching so that the holes punched in the cover match to the holes punched in the associated document.

If further processing, such as binding, is to occur, then the punched document stacks, including punched covers where appropriate, are fed to an accumulator and/or other interface 3021 to a binding module 3023. The interface 3021 between the punch module 3015 and binding module 3023 may be either a custom interface such as when the modules are designed to cooperate, or alternatively by way of a transfer station. The binding module 3023 applies a binding to the punched documents received from the punch module 3015. Such bindings may be comb bindings, wire spiral bindings, polymeric nail-type bindings, or any other type of binding usable to secure punched pages together via cooperating holes. The binding module 3023 optionally receives and uses one or more crimp sets 3025 to define the manner in which a crimped binding is applied.

From the binding module 3023, the bound documents are optionally fed to a cover closer 3027 via a custom interface or transfer station. At this point, the finished documents are passed in a stacked manner to a transfer station, preferably via a book stacker 3029. Note that the finished documents may also be provided to a shingle conveyor 3031 from the cover closer 3027. Also, if binding is not desired, the punched documents may be passed to a stacker 3035 for retrieval from the processing system. At any stage, a user may manually retrieve or place documents as indicated by “manual in/out” component 3033. The user may optionally use a cart 3037, such as described above in detail with respect to FIGS. 1-29, to effect the manual placement or removal of documents.

A flow chart of the actions and motor run sequences for entry and exit of document stacks from a processing system such as described above is shown in FIG. 31. Initially, a lift door is opened at step 3101 allowing access to a lift mechanism. The lift door may be manually actuated but is preferably motor-driven either automatically or in response to a user action. Once a stack is placed through the lift door, then at step 3103, an input belt motor is run to place the stack in position for lifting. Note that as discussed above, there may also be lateral movement, automated or otherwise, of the lift surface or other document-supporting surface to facilitate manual loading and unloading of sheets and/or sheet stacks to and from the processing system. At step 3105, the position of the stack is checked to ascertain whether the stack is appropriately placed for lifting to begin. If it is determined at step 3105 that the stack is not yet properly positioned, then the process reverts to step 3103 to continue running the input belt motor. Otherwise, at step 3107, the input belt motor is stopped, and the lift door is closed.

At step 3109, a run command is issued to commence processing of the stack. The run command may be either automatically issued when the stack is properly positioned after step 3107, or may be manually issued by a user such as through making a selection from a graphical user interface. At step 3111, pursuant to the run command, a lift motor is run at high speed to lift the stack into position for further processing. Subsequently, the vertical position of the stack is checked at step 3113. If the stack is not yet at full height, the process reverts to step 3111, running the lift motor at high speed. Otherwise, at step 3115, the lift motor is slowed to low speed, the main motor is run to process the documents, and the stacker motor is run at low speed to output the processed documents.

From step 3115, the process continues to step 3117, where the document processing is periodically monitored for the occurrence of a sheet jam. If no sheet jam is found to have occurred, the process checks the status of the stack at step 3119 to determine whether the last needed lift has been performed. If it has not, then the process returns to step 3115 and the steps that logically follow. Otherwise, if the last lift has been performed, or if a sheet jam was detected at step 3117, the process moves to step 3121, causing the lift motor to reverse and return the remainder of the stack to the bottom position, causing the main motor to be stopped, and causing the stacker motor to run at high speed, clearing any free papers from the processing apparatus.

At step 3123, the status of the lift is checked, and if the stack is not yet at the bottom position, then the process returns to steps 3121. Otherwise, the process moves to step 3125, whereat the stacker motor is stopped and an access door to the stacker is opened. Once the stacker access door is opened, an output belt motor is run at step 3127 to bring the stack into a position from which a user can access the stack or from which the stack can be moved into a position that is user accessible. As discussed above, there may also be lateral movement of the lift surface, or other document-supporting surface, to facilitate loading and unloading of the stack. The status of the stack is checked at step 3129 to determine whether the stack has exited the process, such as by checking whether any part of the stack has not yet passed the stacker door. If the stack has not yet exited, the process returns to step 3127 where the output belt motor continues to run. Otherwise, at step 3131, the stack motor raises a stack platform on which the stack was most recently sitting back to a top position, ready for processing of another stack.

The logical organization of an exemplary user interface usable to implement an embodiment of the invention is shown schematically in FIG. 32. The primary user interface shown is a visual keypad/touch screen 3201. The keypad/touch screen 3201 allows user entries through a touch-sensitive screen and/or through a standard push button keyboard interface. A screen portion of the keypad/touch screen 3201 presents information visually to the user. Initially, a user is preferably presented with a main screen 3203 showing links to various other screens including a set-up screen 3205, a diagnostic screen 3207, and a menu screen 3209. The user may navigate to any of the screens 3205, 3207, 3209 by selecting an appropriate icon or button at the keypad/touch screen 3201.

Adjustments that may be made preferably include adjustments for sheet width, length, tab adjust, throughput speed, lift size, book size, and/or final die set adjust as shown in adjustments section 3211. As indicated by die set section 3213, the user may set the process so that the necessary die set may be automatically determined and/or adjusted. Note that the interface to the process also includes a non-user interface 3215 for automatically receiving information from sensors, barcodes, and/or other sources and for causing one or more automatic actions in response thereto. The sensors and other information sources illustrated include the following: a sensor that detects a top sheet in a stack, a cart tag that may be automatically recognized, information received over a USB port, a bar code that can be read to determine a desired process etc., information received from a laptop or other computer, information received from a printer, information received by download such as over the Internet, a remote information source, etc. Note that any of the above can supply document content or processing instructions.

All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

It will be appreciated that a novel and useful document processing system has been disclosed herein by way of examples, and that it is the claims, rather than these examples that define the scope of the invention. In particular, preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. 

1. A document handling system for performing at least one operation on successive sheets or stacks of sheets, the document handling system comprising: at least two modules selected from the group consisting of an elevator transfer station, a modular transfer station, a storage station, and a modular processing station for performing an operation on said successive sheets or stacks of sheets, a transportation cart for transporting stacks of sheets between the at least two modules, the transportation cart comprising a plurality of elongated support surfaces disposed substantially parallel one another to collectively present a sheet support surface, said at least two modules each comprising a plurality of elongated support surfaces disposed substantially parallel one another to collectively present a sheet support surface, said module plurality of elongated support surfaces of each said at least two modules and said transportation cart plurality of support surfaces being spaced such that at least a portion of said transportation cart plurality of elongated support surfaces can separately intermesh with the module plurality of support surfaces to create joint sheet support surfaces such that sheets or stacks of sheets disposed on one of the transportation cart plurality of elongated support surfaces or on one of the modules plurality of elongated support surfaces may be transferred to the other of the transportation cart plurality of elongated support surfaces or module plurality of support surfaces, whereby the transportation cart is utilized to move said successive sheets or stacks of sheets between said modules through the document handling system.
 2. The document handling system of claim 1 wherein the elevator transfer station includes a moveable surface that moves the sheets or stacks of sheets in a substantially vertical elevation.
 3. The document handling system of claim 2 wherein the plurality of elongated support surfaces of the elevator transfer station include driven surfaces operable to apply a forward motion to the sheets or stack of sheets to drive the sheets or stack of sheets through the document handling system.
 4. The document handling system of claim 1 wherein the plurality of elongated support surfaces of at least one of the at least two modules includes driven surfaces operable to apply a forward motion to the sheets or stack of sheets to drive the sheets or stack of sheets through the document handling system.
 5. The document handling system of claim 4 wherein the plurality of elongated support surfaces of the modular transfer station include said driven surfaces operable to apply a forward motion to the sheets or stack of sheets to drive the sheets or stack of sheets through the document handling system.
 6. The document handling system of claim 4 wherein the plurality of elongated support surfaces of the modular sheet processing station include said driven surfaces operable to apply a forward motion to the sheets or stack of sheets to drive the sheets or stack of sheets through the document handling system.
 7. The document handling system of claim 3 wherein the driven surfaces include a plurality of driven rollers.
 8. The document handling system of claim 3 wherein the driven surfaces include a plurality of driven belts.
 9. The document handling system of claim 1 wherein the joint sheet support surface is disposed substantially in a joint sheet support plane, and the intermeshed plurality of elongated support surfaces of at least one of the at least two modules is moveable in a plane other than said joint sheet support plane whereby a sheets or stack of sheets disposed on the joint sheet support surface may be transferred to be supported substantially on the plurality of elongated support surfaces of one of the at least two modules by raising or lowering the elongated support surfaces moveable in the plane other than said joint sheet support plane.
 10. The document handling system of claim 1 wherein the modular processing station is selected from the group consisting of a printer, a tab cutter, a binder, a feeder, a cover closer, an envelope stuffer, a punch, a stacker, a laminator, and a sealer.
 11. The document handling system of claim 1 comprising at least a first and a second modular processing station for performing first and second operations on said successive sheets or stacks of sheets.
 12. The document handling system of claim 11 wherein said modular processing stations are disposed and coupled to operate inline such that the first modular processing station performs said first operation on the sheet or stack of sheets, the sheet or stack of sheets is then automatically fed to the second modular processing station, and the second modular processing station then performs said second operation on the sheet or stack of sheets, the first and second modular processing stations being further arranged to operate offline wherein at least one of the first or second modular processing station may be operated to perform said respective operation independent of the remaining modular processing station performing its respective independent operation.
 13. The document handling system of claim 11 wherein said modular processing stations are disposed and coupled to operate inline such that the first modular processing station performs said first operation on the sheet or stack of sheets, the sheet or stack of sheets is then automatically fed to the second modular processing station, and the second modular processing station then performs said second operation on the sheet or stack of sheets, the first and second modular processing stations being further configured to be decouplable from each other, wherein when decoupled at least one of the first or second modular processing station is operable to perform said respective operation independent of the remaining modular processing station.
 14. A document handling system for performing at least one operation on successive sheets or stacks of sheets, the sheet handling system comprising first and second modular processing stations for performing respective first and second operations on said successive sheets or stack of sheets, said modular processing stations being disposed and coupled to operate inline such that the first modular processing station performs said first operation on the sheet or stack of sheets, the sheet or stack of sheets being successively then automatically fed to the second modular processing station, and the second modular processing station then performing the second operation on the sheet or stack of sheets, the first and second modular processing stations being further arranged and adapted to operate offline wherein at least one of the first or second modular processing station may be operated to perform said respective operation independent of the remaining modular processing station performing its respective independent operation.
 15. The document handling system of claim 14 further comprising at least one module selected from the group consisting of an elevator transfer station, a modular transfer station, a storage station, a transportation cart, and a further modular processing station for performing an operation on said successive sheets or stacks of sheets, said at least one module interfacing with at least one of the first or second modular processing station.
 16. The document handling system of claim 11, further comprising at least one modular transfer station disposed inline between the first and second modular processing stations such that the modular transfer station acts as a buffer to hold said sheet or stack of sheets processed by the first modular processing station until such time as the second processing station is operable to perform the second operation on said sheet or stack of sheets.
 17. An interface to a document processing system comprising at least two cooperating modules selected from the group consisting of an elevator transfer station, a modular transfer station, a storage station, a transportation cart, and a modular sheet processing station, wherein a transfer of sheets or stacks of sheets between the cooperating modules is facilitated by the intermeshing of a plurality of elongated support surfaces extending from each of the cooperating modules, the interface being at least partially actuatable by a user, the interface comprising: a user interface portion for allowing interaction of the user with the document processing system; and an automatic interface portion for automatically receiving information in device-readable form.
 18. An interface to a document processing system comprising at least two cooperating modular sheet processing stations, wherein the cooperating modular sheet processing stations are disposed and coupled for inline processing of sheets or sheet stacks and, while coupled, to allow the offline use of at least one of the cooperating modular sheet processing stations, the interface being at least partially actuatable by a user, the interface comprising: a user interface portion for allowing interaction of the user with the document processing system, and for initiating the offline use of at least one of the cooperating modular sheet processing stations; and p1 an automatic interface portion for automatically receiving information in device-readable form.
 19. The interface according to claim 17, wherein the user interface portion includes a display portion and a user input portion, wherein the display portion displays to the user at least one type of information selected from document processing set up information, document processing system diagnostic information, and user input information.
 20. The interface according to claim 19, wherein the user input portion comprises a touch screen.
 21. The interface according to claim 20, wherein the touch screen is integral with the display portion of the user interface portion.
 22. The interface according to claim 19, wherein the user input portion comprises a keypad.
 23. The interface according to claim 17, wherein the automatic interface portion is configurable to receive information from at least one of a sensor input, a barcode reader input, and a digital electronic input.
 24. The interface according to claim 23, wherein the sensor input indicates the presence of a sheet in an input stack.
 25. The interface according to claim 23, wherein the sensor input indicates the presence of a cart for transporting sheets or stacks of sheets.
 26. The interface according to claim 23, wherein the information receivable from the barcode reader input comprises an indication of a desired document processing operation.
 27. The interface according to claim 23, wherein the digital electronic input comprises a USB port.
 28. The interface according to claim 23, wherein the information receivable from the digital electronic input comprises information from at least one of a printer, a computer, and the Internet.
 29. A transportation cart for moving stacks of sheets between processing modules in a sheet handling system, the sheet handling system comprising at least two modules selected from the group consisting of an elevator transfer station, a modular transfer station, a storage station, and a modular processing station for performing an operation on said successive sheets or stacks of sheets, said at least two modules each comprising a plurality of elongated support surfaces disposed substantially parallel one another to collectively present a sheet support surface, the transportation cart comprising a plurality of elongated support surfaces disposed substantially parallel one another to collectively present a sheet support surface, said module plurality of elongated support surfaces of said at least two modules and said transportation cart plurality of support surfaces being spaced and disposed such that at least a portion of said transportation cart plurality of elongated support surfaces can separately intermesh with the module plurality of support surfaces of each of said at least two modules, respectively, to create joint sheet support surfaces such that sheets or stacks of sheets disposed on one of the transportation cart plurality of elongated support surfaces or on the module plurality of elongated support surfaces may be transferred to the other of the transportation cart plurality of elongated support surfaces or module plurality of support surfaces, the transportation cart further comprising a securing arrangement that selectively holds the stack of sheets in position on the sheet support surface during movement whereby the transportation cart is utilized to move said successive sheets or stacks of sheets between said modules through the document handling system.
 30. The transportation cart of claim 29 further comprising wheels for movement of the cart.
 31. The transportation cart of claim 30 wherein the wheels are in the form of rollers.
 32. The transportation cart of claim 30 wherein the wheels are in the form of casters.
 33. The transportation cart of claim 30 further comprising a handle for imparting movement to the transportation cart.
 34. The transportation cart of claim 30 wherein the securing arrangement comprises at least one upright and a substantially horizontal portion that is movable between a position wherein the horizontal portion contacts the stack of sheets to secure the stack to the sheet support surface and a position wherein the horizontal portion does not contact the stack of sheets such that the stack may be transferred to one of the modules.
 35. The transportation cart of claim 34 wherein the securing arrangement comprises a pair of uprights and the horizontal portion extends between the uprights.
 36. The transportation cart of claim 30 wherein the securing arrangement comprises a belt.
 37. The transportation cart of claim 30 wherein at least one of the cart elongated support surfaces or the module elongated support surfaces are selectively movable in substantially vertical direction to facilitate transfer of a stack of sheets supported on the elongated support surfaces of either the cart or the module to the elongated supported support surfaces of the other of the cart or the module.
 38. The transportation cart of claim 30 wherein the cart elongated support surfaces are selectively movable in substantially vertical direction to facilitate transfer of a stack of sheets supported on the elongated support surfaces of either the cart or the module to the elongated supported support surfaces of the other of the cart or the module.
 39. The transportation cart of claim 38 further comprising a housing.
 40. The transportation cart of claim 39 wherein the housing is selectively moveable in the substantially vertical direction whereby the cart elongated support surfaces are movable in the substantially vertical direction.
 41. The transportation cart of claim 39 wherein the cart elongated support surfaces are movable in the substantially vertical direction relative to the housing.
 42. A document handling system for performing at least one operation on successive sheets or stacks of sheets, the paper handling system comprising: at least two modular processing stations for performing a first operation and a second operation on said successive sheets or stacks of sheets, at least one modular transfer station disposed inline between the first and second modular processing stations such that the modular transfer station acts as a buffer to hold said sheet or stack of sheets processed by the first modular processing station until such time as the second processing station is operable to perform the second operation on said sheet or stack of sheets, said at least two modular processing stations and at least one modular transfer station each comprising a plurality of elongated support surfaces disposed parallel one another to collectively present a sheet support surface, at least a portion of said plurality of elongated support surfaces of the at least two modular processing stations being disposed to intermesh to create a joint sheet support surface such that sheets or stacks of sheets disposed on one such plurality of elongated support surfaces on one of the at least two modules may be transferred to the plurality of elongated support surfaces on another of the at least two modules, whereby said successive sheets or stacks of sheets are moved through the document handling system. 